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41.
BackgroundClinical prediction rules (CPRs) to identify children with serious infections lack validation in low-prevalence populations, which hampers their implementation in primary care practice.AimTo evaluate the diagnostic value of published CPRs for febrile children in primary care.MethodAlarm signs of serious infection and clinical management were extracted from routine clinical practice data and manually recoded with a structured electronic data-entry program. Eight CPRs were selected from literature. CPR-variables were matched with alarm signs and CPRs were applied to the GPC-population. ‘Referral to emergency department (ED)’ was used as a proxy outcome measure for ‘serious infection’. CPR performance was assessed by calibration analyses, sensitivity, specificity, and area under the ROC-curve (ROC-area).ResultsA total of 9794 GPC-contacts were eligible, 54% male, median age 2.3 years (interquartile range 1.0–4.6 years) and 8.1% referred to ED. Frequencies of CPR-variables varied from 0.5% (cyanosis, drowsy) to 25% (temperature ≥40°C). Alarm signs frequently included in CPRs were ‘ill appearance’, ‘inconsolable’, and ‘abnormal circulatory or respiratory signs’. The height of the CPR’s predicted risks generally corresponded with being (or not being) referred to the ED in practice. However, calibration-slopes indicated that three CPRs underestimated the risk of serious infection in the GPC-population. Sensitivities ranged from 42% to 54%, specificities from 68% to 89%. ROC-areas ranged from 0.52 to 0.81, with best performance of CPRs for children aged <3 months.ConclusionPublished CPRs performed moderately well in the primary out-of-hours care population. Advice is given on how to improve translation of CPRs to primary care practice.  相似文献   
42.
Loss-of-function variants in ANKRD11 were identified as the cause of KBG syndrome, an autosomal dominant syndrome with specific dental, neurobehavioural, craniofacial and skeletal anomalies. We present the largest cohort of KBG syndrome cases confirmed by ANKRD11 variants reported so far, consisting of 20 patients from 13 families. Sixteen patients were molecularly diagnosed by Sanger sequencing of ANKRD11, one familial case and three sporadic patients were diagnosed through whole-exome sequencing and one patient was identified through genomewide array analysis. All patients were evaluated by a clinical geneticist. Detailed orofacial phenotyping, including orthodontic evaluation, intra-oral photographs and orthopantomograms, was performed in 10 patients and revealed besides the hallmark feature of macrodontia of central upper incisors, several additional dental anomalies as oligodontia, talon cusps and macrodontia of other teeth. Three-dimensional (3D) stereophotogrammetry was performed in 14 patients and 3D analysis of patients compared with controls showed consistent facial dysmorphisms comprising a bulbous nasal tip, upturned nose with a broad base and a round or triangular face. Many patients exhibited neurobehavioural problems, such as autism spectrum disorder or hyperactivity. One-third of patients presented with (conductive) hearing loss. Congenital heart defects, velopharyngeal insufficiency and hip anomalies were less frequent. On the basis of our observations, we recommend cardiac assessment in children and regular hearing tests in all individuals with a molecular diagnosis of KBG syndrome. As ANKRD11 is a relatively common gene in which sequence variants have been identified in individuals with neurodevelopmental disorders, it seems an important contributor to the aetiology of both sporadic and familial cases.  相似文献   
43.
Thirteen cases of autoimmune hepatitis (AIH) were diagnosed from 1990 to 2003 in the area of the Hospital de Sagunto (Valencia, Spain), which attends a population of 112,003 inhabitants aged more than 14 years (54,622 males and 57,381 females). The diagnostic criteria of the International Autoimmune Hepatitis Group were used and patients who, despite having a probable diagnosis of AIH, presented hepatitis C virus infection were excluded. The diagnosis was probable in one patient and definitive in 12. All patients, 11 females and two males aged 45.9 12.2 years (range: 28-66), were classified as AIH type 1. Among the population aged more than 14 years, the mean annual incidence of AIH was 0.83 cases/100,000 inhabitants (95% CI, 0.44-1.42) (range: 0-2.68), showing a significant trend to increase (b = 0.132; p = 0.019). The incidence was higher in women than in men (RR = 5.24; 95% CI, 1.16-23.62). The mean annual incidence was 1.37 (95% CI, 0.68-2.46) (range: 0-3,49) in women and was 0.26 (95% CI, 0.02-0.96) (range: 0-1.83) in men. By age, the maximum mean annual incidence was observed in the group aged 55-64 years (1.6 cases/100,000 inhabitants). The prevalence of AIH in September 2003 was 11.61 cases/100,000 inhabitants aged more than 14 years (95% CI, 6.78-19.86). The prevalence was 3.66 (95% CI, 1-13.35) in men and was 19.17 (95% CI, 10.70-34.33) in women.  相似文献   
44.
Altered mesolimbic dopamine signaling has been widely implicated in addictive behavior. For the most part, this work has focused on dopamine within the striatum, but there is emerging evidence for a role of the auto-inhibitory, somatodendritic dopamine D2 receptor (D2R) in the ventral tegmental area (VTA) in addiction. Thus, decreased midbrain D2R expression has been implicated in addiction in humans. Moreover, knockout of the gene encoding the D2R receptor (Drd2) in dopamine neurons has been shown to enhance the locomotor response to cocaine in mice. Therefore, we here tested the hypothesis that decreasing D2R expression in the VTA of adult rats, using shRNA knockdown, promotes addiction-like behavior in rats responding for cocaine or palatable food. Rats with decreased VTA D2R expression showed markedly increased motivation for both sucrose and cocaine under a progressive ratio schedule of reinforcement, but the acquisition or maintenance of cocaine self-administration were not affected. They also displayed enhanced cocaine-induced locomotor activity, but no change in basal locomotion. This robust increase in incentive motivation was behaviorally specific, as we did not observe any differences in fixed ratio responding, extinction responding, reinstatement or conditioned suppression of cocaine, and sucrose seeking. We conclude that VTA D2R knockdown results in increased incentive motivation, but does not directly promote other aspects of addiction-like behavior.  相似文献   
45.
OBJECTIVE: The forecasted shortage of nurses specialized in intensive care seriously threatens the service level in the intensive care units (ICUs). This problem might partly be solved by introducing nurses without ICU experience who can provide basic nursing care to relieve the workload of the ICU nurses. This prospective controlled study was set up to determine whether such an introduction causes a significant shift in the quality of care. DESIGN: A prospective observational study was conducted to measure possible changes in the quality of care by examining the number of predefined nursing errors per patient with an observational instrument, the Critical Nursing Situation Index (CNSI). The CNSI was randomly applied during a preassessment period, an intervention period, and a postassessment period. During the intervention period, 16 full time equivalent nurses were employed with the assignment to assist the ICU nurses with basic care activities for 6 months. SETTING: The study was conducted in a 30-bed ICU at the Academic Medical Center in Amsterdam. ANALYSIS: The effect of the employment of nurses was expressed as the difference in the incidence of CNSI scores between the preassessment period and the intervention period on the basis of the relative risk ratios. The results of the comparison between the preassessment and the postassessment period were used to express the consistency of the measure. RESULTS: The researchers completed 600 CNSI observations in 256 patients in 162 days. Overall incidence rates during the preassessment (13%; 1539/12 222) and postassessment (14%; 1554/11 327) period were comparable, whereas the intervention period showed a diminished overall incidence of 9% (1019/11 395). The overall relative risk (95% CL) was 0.70 (0.56/0.86), indicating a significant risk reduction during the intervention period. CONCLUSION: The employment of nurses without ICU training improved the quality of care. This positive effect was primarily explained by the increase in available nursing time.  相似文献   
46.
The pharmacokinetics of human recombinant plasminogen activator inhibitor-1 (rPAI-1) was studied in rabbits. Latent rPAI-1 (0-2 units of tissue-type plasminogen activator neutralizing activity per microgram protein); reactivated rPAI-1 (approximately 150 units/micrograms); and chloramine T-oxidized, nonreactivatable rPAI-1 (approximately 0.7 units/microgram) were studied. The pharmacokinetic parameters for the disposition of rPAI-1 antigen after an intravenous bolus injection of 1.0 or 2.5 mg/kg rPAI-1 were very similar for all three forms: the initial volume of distribution was approximately 60 ml/kg, the initial half-life in plasma was 6 minutes, and the plasma clearance was approximately 4 ml/kg/min. The disposition of PAI activity after injection of reactivated rPAI-1 was similar to that of rPAI-1 antigen. Injection of latent rPAI-1 was associated with a nearly threefold increase in the specific activity of circulating PAI-1 from 2 units/micrograms to 5.0 +/- 1.1 units/micrograms (p less than 0.01) within 1 minute, followed by a cumulative 25-fold increase in specific activity over 1 hour (p = 0.01). In contrast, the specific activity of oxidized or reactivated preparations of rPAI-1 did not increase in the first several minutes after injection. These findings support the existence of a fast-acting but low-capacity mechanism for the reactivation of rPAI-1 in vivo.  相似文献   
47.
HYPOTHESIS AND OBJECTIVES: the hypothesis of this study is that genes involved in the regulation of the immune system, expressed by HLA antigens and anti-neutrophil cytoplasmic antibodies (ANCA), could be determinants of disease susceptibility and behavior in inflammatory bowel disease (IBD). MATERIAL AND METHOD: seventy patients with a diagnosis of inflammatory bowel disease, 46 with ulcerative colitis and 24 with Crohn"s disease were included. HLA class I (A and B) and II (DR) antigens were studied by serological techniques. Detection of ANCA was carried out in all patients by an indirect immunofluorescence method. The relative frequencies of HLA antigens were compared with a control group made up of 156 blood donors. The control group for the ANCA study was made up of 100 individuals. RESULTS: we found a significant increased frequency of HLA-DR2 in patients with ulcerative colitis. No significant differences were found between patients with Crohn"s disease and controls regarding HLA typing. We detected a significant increase of HLA-DR3 in extensive forms of ulcerative colitis. Detection of ANCA was positive in 46% of the patients with ulcerative colitis and in 12% of the patients with Crohn"s disease (p <0.05). We observed an increased frequency of ANCA in patients with UC and HLA-DR2 (p = 0.15). CONCLUSIONS: the association found between HLA-DR3 and extensive forms of ulcerative colitis provides evidence of genetic heterogeneity. The relationship between ANCA and HLA phenotype (although not significant) supports this concept.  相似文献   
48.
49.
Alteration of the TAL1 locus is the most common nonrandom genetic defect in childhood T-cell acute lymphoblastic leukemia (T-ALL). To determine if rearrangements of the TAL1 proto-oncogene confer a distinct leukemic phenotype, we studied leukemic peripheral blood or bone marrow samples from 182 children with newly diagnosed T-ALL enrolled on Pediatric Oncology Group treatment protocols. Forty-eight (26%) of the samples had a local rearrangement of the TAL1 locus. Demographic and clinical features were compared for patient subgroups with and without TAL1 rearrangements. The only clinical correlates that were significantly associated with TAL1 gene rearrangements were higher white blood cell count (P = .017) and higher hemoglobin (P = .007) at diagnosis. Immunophenotypically, samples with altered TAL1 were more likely to be CD2+ (P = .001) and lack CD10 (cALLa) expression (P = .007) than those without the rearrangement. There was a trend toward improved event-free survival (EFS) in patients with TAL1 rearrangements (4-year EFS was 44% +/- 7% for patients without the rearrangements v 59% +/- 11% for those with rearrangements), but the difference was not significant (P = .34). The role of TAL1 in leukemogenesis has yet to be clearly defined, and the prognostic significance of TAL1 gene rearrangements in T-ALL deserves further study.  相似文献   
50.
Two B-cell lines, 2F7 and 10C9, were established by single cell cloning from biopsies obtained from two acquired immune deficiency syndrome patients with Burkitt's lymphoma. Representation of the original tumors was verified by demonstration of (1) identical biallelic rearrangement of Ig genes for 2F7 and (2) shared idiotype for 10C9. Both cell lines displayed cell-surface Ig and secreted Ig (IgM lambda for 2F7, IgM kappa for 10C9). IgMs from both cell lines immunoprecipitated actin; in addition, 2F7 IgM lambda immunoprecipitated recombinant human immunodeficiency virus type 1 (HIV-1) gp 160. 2F7 IgM lambda did not react with other autoantigens (double-stranded and single-stranded DNA, actin, bovine serum albumin, IgG), whereas 10C9 IgM kappa reacted with human IgG. The 2F7 IgM heavy-chain variable region (VH) showed a 95% nucleotide homology with a previously sequenced VHIII germline gene, hv3019b9, whereas the 10C9 IgM VH showed a 95% homology with a previously sequenced VHIV germline gene, VH4.21. Use of minimally modified VH genes and demonstration of reactivity with chronically present antigens (ie, actin, HIV-1 gp 160, or human IgG) suggests that B cells in HIV-1-infected individuals proliferating in response to chronic antigenic stimulation may be at increased risk for lymphomagenesis.  相似文献   
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